i introduced my male betta a week ago and i thought i needn't have worried. He swam around with the other fish/inhabitants as placid as can be. Then he suddenly changed over night. After a week of being fine, he has started flaring at his reflection in the glass all the time, then started to attack it, bumping his head against the glass. Now he has started being agressive to his tankmates. i'm not worried about them in that i know they are too quick and too big for him, and the frogs can certainly hold their own, but i don't want everybody stressed. It was all so calm just a day ago. Is this just a phase? Why would he be fine and suddenly become such a grump? i'm uncomfortable taking him out as he'd have to be without a heater but what should/can i do?? He went in last to prevent this from happening but it's like he's over night decided this is HIS tank. Help??